Your Digest for Friday, Mar 29, 2024 10:59 PM


Fascicular blocks

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[!TIP] Mnemonics
Left fascicular block will cause axis deviation 'away' from the blocked fascicle
Posterior block will cause q wave in inferior leads ("postero-inferior")
Anterior block will cause q waves in lateral leads (?except lead I) - ("Anterolateral")

LAFB (Left anterior block)) LPFB (Left posterior block)
Axis -45 to 90 (i.e Left axis dev.) +90 to +180 (i.e Right axis dev)
QRS duration < 0.12 (but slightly prolonged) QRS < 0.12
aVL, V5 and V6 shows QR complexes I,aVL shows rS complexes
II, III and aVF show rS complexes II,III,aVF Shows qR complexes.
(q Waves in III and aVF is mandatory)

Bifascicular block
= LAFB with RBBB

"Bifascicular block is the combination of RBBB with either LAFB or LPFB" Source

Trifascicular blocks


[!TIP] Mnemonic: Light, liver, lungs, levothyroxine
Light - cataracts, photosensitivity
Liver - steatohepatitis
Lungs - fibrosis
Levothyroxine - hypothyroidism or hyperthyroidism (levothyroxine is just a mnemonic because it has L)

Acute Chronic
CHB Lung fibrosis
QT prolongation -> Arrhythmias Steatohepatitis
Thrombophlebitis if given in peripheral vein Hypo / Hyperthyroidism
Photosensitive slate gray rash
Cataracts
Sensory and motor neuropathy

From pass medicine:

Mnemonics:

Anti-Ri (Rieally blurry vision)
Anti GAD GAAAAD he's stiff (stiff man syndrome)
Anti-Hu who kicked my chair (pain) and then fell over (ataxia)
Anti yo- Yo lady give me back my danish (cerebellar syndrome, lady for breast + ovarian)


Erythrasma

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[!INFO] My classification
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Wernicke encephalopathy

[!TIP] Kor - chronic, confabulations


[!TIP] mnemonic: DNAAB



Alcohol is a common cause.
CKD, Cystic fibrosis, haemochromatosis, Obstruction, trauma, recurrent acute pancreatitis, hypercalcemia, autoimmune are all causes. Source
Also pancreatic structural abnormalities like pancreas divisum and annular pancreas.
Diagnosis:

There is loss of endocrine and exocrine function but significant failure occurs only after many years.


Causes of methaemoglobinemia

Hereditary:

[!INFO] Gallavardin phenomenon
A mid-systolic ejection murmur, heard best over the right second intercostal space, with radiation into the right neck. However, high-frequency components may radiate to the apex in calcified aortic valves, and this phenomenon is called the Gallavardin phenomenon. Source

Acute AR Chronic AR
Very rare Common
Dissection Degeneration +/- bicuspid valve. (bicuspid AR is the commonest congenital heart lesion in humans)
Bicuspid AV is the commonest cause for isolated AR.
Infective endocarditis infective endocarditis
Trauma
Myxomatous degeneration (due to Ehlers Danlos or Marfans)
Rheumatic heart disease (Now becoming less common in developed nations)
Ankylosing spondylytis -> aoritc root aortitis -> AR
Aortic regurgitation is the most frequent complication of syphilitic aortitis (>60%)

1 unit = half a pint of beer

Cryoglobulinaemia

#2015OCT-BOF/Q10

suspected in patients presenting with arthralgia, purpura, skin ulcers, glomerulonephritis, and peripheral neuropathy.


  1. Beta blockers - see [[#Beta blocker pharmacology]] below
    1. First line anti anginal medications; Initial step in angina management is "beta blocker montherapy." Beta blockers are the ⭐only antianginals proven to reduce reinfarction and reduce mortablity.
    2. Mechanism: reduce heart rate and contractility -> reduced oxygen demand -> therefore delay the onset of angina during exercise. Also reduced LV wall stress by their antihypertensive action.
    3. Contraindicated in prinz-metal angina; unopposed alpha action may exacerbate coronary vasospasm.
  2. CCBs
    1. rate liming Non-dihydropyridines are preferred when used as monotherapy.
    5. Mechanism: Coronary and peripheral vasodilation and reduced contractility.
    7. Most probably no mortality benefit Source

The visual field loss is typically peripheral with nerve fiber bundle type defects predominating. Central defects occur in more advanced disease.
Known causes of IIH:
1. tetracyclines including doxycyline and minocycline.
2. Hypervitaminosis A (excessive dietary intake / retinoic acid, isotretinoin)
1. Avoid eating polar bear liver. ;) Source
3. COCP
4. Lithium
- chronic infection: Hep C, especially when Hep C leads to [[2022 General Medicine Paper-May#Cryoglobulinaemia|Cryoglobulinaemia]] (C for Cryo), Tuberculosis, Subacute Infective endocarditis


[[2022 General Medicine Paper-May#Cryoglobulinaemia]]

Preference of prescription of drugs in heart failure (HFrEF)

[!TIP] Mnemonic: SSL


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Source


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[!INFO] Respiratory alkalosis
Respiratory alkalosis followed by metabolic acidosis is characteristic of salicylate poisoning.

Symptoms include


can cause [[2022 General Medicine Paper-May#Cryoglobulinaemia|Cryoglobulinaemia]].


Colorectal cancer syndromes

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Classification base on presence of pre-existing polyposis: (genes in Brackets)

Pre-existing polyposis Pre-existing hamartomatous polyps No pre-existing polyposis
FAP (APC) - 100% Cancer risk Peutz-Jeghers - 40% cancer risk HNPCC - aka Lynch syndrome Type 1 and Type 2 (MLH1) - 80% cancer risk
Gardner's (APC) Juvenile polyposis
Cowdens' syndrome (PTEN)
Source
Source
Source
Further reading: Source

Alkaptonuria

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Source

Waterhouse-Friederichsen syndrome

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Bilateral adrenal haemorrhage most commonly due to meningococcal septicaemia.
Usually fatal within 24 to 48 hours.
Majority occurs in children.
Source